Thrombosis is a primary method of failure for artificial or mechanical cardiovascular biomaterials, such as heart valves. Thrombosis refers to the undesirable coagulation of blood at or near the surface of such a structure. Current mechanical heart valves have demonstrated improved mechanical properties and durability. However, the constant contact of mechanical heart valves with blood sometimes leads to the formation of blood clots following undesirable thrombosis. Thus, thrombosis and blood clotting is a major concern in mechanical biomaterial design, including particularly heart valve design.
To prevent thrombosis, it is common to place patients upon long-term anticoagulation therapy. However, such therapy is expensive, and may pose other risks or side effects. Thus, anticoagulation therapy is not an ideal solution.
Every year, it is estimated that over 150,000 heart valve replacement surgeries are performed, with more than half occurring in the United States alone. When a natural heart valve becomes diseased and is no longer able to function properly, valve replacement therapy may be necessary. The most commonly replaced valves are the aortic and mitral. Success rates for valve replacement surgeries have risen, and surgeons currently are likely to employ replacement as a treatment for damaged natural valves.
What is needed in the industry and in the medical community is an improved biomaterial that is less prone to undesirable thrombosis. Also, a method of constructing a suitable biomaterial which lessens the incidence of undesirable blood clotting would be very desirable. In particular, a mechanical heart valve that reduces the incidence of thrombosis when surgically implanted is needed.